changing current thread's classloader - when does this matter

[Suma Rangaraj]

Hello all -

I know that class loader is used for dynamically loading classes into the existing class loader to be able to create instances in the current classloader.

Take this code segment for instance -

ClassLoader current_classloader = Thread.currentThread().getContextClassLoader();

// lets say you have an instance that belongs to a different classloader and the instance is available here.
Object myobj // myobj's classloader is different than current_classloader

Thread.currentThread().setContextClassLoader(myobj.getClassLoader());

//run a method on myobj
myobj.mymethod();

my question is is the following line of code necessary - if so under what conditions?

Thread.currentThread().setContextClassLoader(myobj.getClassLoader());

Thanks for help.